The tense of a verb shows the time of an action or event. English has three tenses: the past, the present and the future. Each of these three tenses are further divided into four.

Present Tenses

Simple present tense
Present continuous tense
Present perfect tense
Present perfect continuous tense
Past tenses

Simple past tense
Past continuous tense
Past perfect tense
Past perfect continuous tense

Future tenses

Simple future tense
Future continuous tense
Future perfect tense
Future perfect continuous tense

The present tense is used to talk about time now; the past tense is used to talk about time then; the future tense is used to talk about the time to come.